Sains Malaysiana 48(1)(2019): 15–21

http://dx.doi.org/10.17576/jsm-2019-4801-03

 

Effects of Rainfall, Number of Male Inflorescences and Spikelets on the Population Abundance of Elaeidobius kamerunicus (Coleoptera: Curculionidae)

(Kesan Hujan, Bilangan Jambak Bunga Sawit Jantan dan Spikelet ke atas Kelimpahan Populasi Elaeidobius kamerunicus (Coleoptera: Curculionidae))

NURUL FATIHAH, A.L.1*, MUHAMAD FAHMI, M.H.1, LUQMAN, H.A.1, SYARIFAH NADIAH, S.M.D.1, TEO, T.M.2, IZFA RIZA, H.1 & IDRIS, A.B.1

 

1Centre for Insect Systematic, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

2Advanced Agriecological Research Sdn. Bhd., No 11, Jalan Teknologi 3/6, Taman Sains Selangor 1, Kota Damansara, 47810 Petaling Jaya, Selangor Darul Ehsan, Malaysia

 

Diserahkan: 30 Mac 2018/Diterima: 4 September 2018

 

ABSTRACT

Elaeidobius kamerunicus was first introduced to Malaysia from Cameroon as an oil palm pollinator in 1981. Since then, oil palm pollination has improved and the need for assisted pollination has reduced. Fruit set development and fruit production also saw significant improvements, until a reported decline that began in the late 1980s. Several factors may have contributed to such decline, but most researchers believe it is due to the low E. kamerunicus population. Therefore, a study was conducted to determine whether the amount of rainfall and the number of male inflorescences and spikelets influenced the population abundance of E. kamerunicus in Ladang Lekir, Perak, Malaysia. Sampling was performed each month in oil palm subplots, three for each age of palm age, from October 2015 to September 2016. A total of nine spikelets (three from the top, middle and base of a male inflorescence) were randomly selected from each male inflorescence on each chosen palm. They were cut early in the morning to avoid the weevil’s most active time, thus making collection easier. The number of weevils congregating on each spikelet was then counted. The average number of E. kamerunicus per hectare (ha) living on oil palms aged four and six were 21,086 and 25,712, respectively. The amount of rainfall and the number of male inflorescences and spikelets were found to positively correlate with the E. kamerunicus population. The number of male inflorescences showed strong correlation with the E. kamerunicus population. However, in-depth study is needed to determine the relationship between E. kamerunicus and fruit set.

 

Keywords: Coleoptera; Elaeidobius kamerunicus; oil palm; oil palm pollinator; population abundance

 

ABSTRAK

Elaeidobius kamerunicus mula diperkenalkan ke Malaysia dari Cameroon sebagai serangga pendebunga kelapa sawit pada tahun 1981. Sejak daripada itu, pendebungaan kelapa sawit bertambah baik dan keperluan untuk pendebungaan berbantu telah berkurang. Pembentukan set buah dan pengeluaran buah juga menunjukkan peningkatan yang ketara, sehingga terdapat laporan penurunan bermula pada akhir 1980-an. Beberapa faktor mungkin menyumbang kepada kemerosotan pendebungaan ini tetapi kebanyakan penyelidik percaya kemerosoton ini disebabkan oleh kelimpahan populasi E. kamerunicus itu sendiri. Oleh itu, satu kajian telah dijalankan untuk menentukan sama ada jumlah hujan, bilangan jambak bunga sawit jantan dan spikelet mempengaruhi kelimpahan populasi E. kamerunicus di Ladang Lekir, Perak, Malaysia. Pensampelan dilakukan pada setiap bulan di subplot kelapa sawit, tiga untuk setiap umur kelapa sawit, dari Oktober 2015 hingga September 2016. Sebanyak sembilan spikelet (tiga dari atas, tengah dan bawah bunga sawit jantan) telah dipilih secara rawak daripada setiap bunga sawit jantan matang yang dipilih. Spikelet dipotong pada awal pagi untuk mengelakkan waktu paling aktif kumbang pendebunga supaya proses pensampelan menjadi mudah. Bilangan kumbang yang terkumpul di setiap spikelet bunga jantan matang kemudiannya dihitung. Purata kelimpahan populasi E. kamerunicus setiap hektar pokok kelapa sawit berumur 4 dan 6 tahun masing-masing adalah 21,086 dan 25,712 kumbang. Jumlah hujan, bilangan jambak bunga sawit jantan dan spikelet didapati berkorelasi positif dengan populasi E. kamerunicus. Bilangan jambak bunga sawit jantan menunjukkan korelasi yang kuat dengan populasi E. kamerunicus. Walau bagaimanapun, kajian yang lebih mendalam diperlukan untuk menentukan hubungan antara E. kamerunicus dengan set buah.

 

Kata kunci: Coleoptera; Elaeidobius kamerunicus; kelapa sawit; kelimpahan populasi; pendebunga kelapa sawit

RUJUKAN

Basri, M.W. & Norman, K.H. 1997. Role and effectiveness of Elaeidobius kamerunicus, Thrips hawaiiensis and Pyroderces sp. in pollination of mature oil palm in Peninsular Malaysia. Elaeis 9(1): 1-16.

Basri, M.W., Masijan, Z., Halim, A.H. & Tayeb, D.M. 1987. The population census and the pollination efficiency of the weevil, Elaeidobius kamerunicus in Malaysia - A status report, 1983-1986. In Proceeding of the 1987 International Oil Palm/Palm Oil Conferences. Progress and Prospect. 23 June-1 July 1987. Palm Oil Research Institute of Malaysia, Kuala Lumpur. pp. 535-549.

Chee, K.H. & Chiu, S.B. 1999. The oil palm pollinating weevil, Elaeidobius kamerunicus in Malaysia-A review. Planter 75(877): 187-198.

Dhileepan, K. 1992. Pollen carrying capacity, pollen load and pollen transferring ability of the oil palm pollinating weevil, Elaeidobius kamerunicus Faust in India. Oleagineux 47(2): 55-61.

Dhileepan, K. 1994. Variation in populations of the introduced pollinating weevil (Elaeidobius kamerunicus) (Coleoptera: Curculionidae) and its impact on fruitset of oil palm (Elaeis guineensis) in India. Bulletin of Entomological Research 84: 477-485.

Donough, C.R., Chew, K.W. & Law, I.H. 1996. Effect of fruit set on OER and KER: Results from studies at Pamol Estates (Sabah) Sdn. Bhd. Planter 72(841): 203-219.

Eardley, C., Roth, D., Clarke, C., Buchmann, S. & Gemmill, B. 2006. Pollinators and Pollination: A Resource Book for Policy and Practice. African Pollinator Initiative (API), Pretoria, South Africa.

Ednan, S.W. 2010. Dinamika populasi kumbang Elaeidobius kamerunicus (Curculionidae: Coleoptera) sebagai penyerbuk kelapa sawit (Elaeis guineensis Jacq.) umur enam tahun. Thesis, Institut Pertanian Bogor, Indonesia (Unpublished).

Hardon, J.J. & Turner, P.D. 1967. Observations on natural pollination in commercial plantings of oil palm, (Elaeis guineensis) in Malaya. Experimental Agriculture 3(2): 105-116.

Matthew, S.L. & Matthew, D.P. 2011. Microclimate and habitat heterogeneity through the oil palm lifecycle. Basic and Applied Ecology 12: 540-551.

Mega, S.A. 2011. Demografi dan populasi kumbang Elaeidobius kamerunicus Faust (Coleoptera: Curculionidae) sebagai penyerbuk kelapa sawit (Elaeis guineensis Jacq) di perkebunan PT. Agri Andalas, Provinsi Bengkulu. Thesis, Institut Pertanian Bogor, Indonesia (Unpublished).

Poinar, G.O., Jackson, T.A., Bell, N.L. & Wahid, M.B. 2002. Elaeolenchus parthenonema n.g., n.sp. (Nematoda: Sphaerularioidea: Anandranematidae n. fam.) parasitic in the palm-pollinating weevil Elaeidobius kamerunicus Faust, with a phylogenetic synopsis of the Sphaerularioidea Lubbock, 1861. Systematic Parasitology 52(3): 219-225.

Ponnamma, K. 1999. Diurnal variation in the population of Elaeidobius kamerunicus on the anthesising male inflorescences of oil palm. Planter 75(881): 405-410.

Prasetyo, A.E., Supriyanto, E., Susanto, A. & Purba, A.R. 2010. Population dynamics of Elaeidobius kamerunicus Faust, a case study on upland oil palm plantation. Proceeding of the International Conference of Oil Palm. Kuala Lumpur, Malaysia.

Prasetyo, A.E., Purba, W.O. & Susanto, A. 2014. Elaeidobius kamerunicus: Application of hatch and carry technique for increasing oil palm fruit set. Journal of Oil Palm Research 26(3): 195-202.

Rizuan, Z.A., Hisham, N.H. & Shamsudin, A. 2013. Role of pollinating weevil (Elaeidobius kamerunicus), seasonal effect and its relation to fruit set in oil palm area of FELDA. Proceeding of PIPOC 2013 International Palm Oil Congress. KLCC, Kuala Lumpur, Malaysia, 19-21 November 2013.

Sambathkumar, S. & Ranjith, A.M. 2011. Insect pollinators of oil palm in Kerala with special reference to African weevil, Elaeidobius kamerunicus Faust. Pest Management in Horticultural Ecosystem 17(1): 14-18.

Sugih, W., Setyobudi, H., Achmad, F. & Thiagarajan. 1996. Influence of rainfall, palm age and assisted pollination on oil palm fruitset in Riau, Indonesia. Proceeding of the International Palm Oil Congress: Competitiveness for the 21st Century. Palm Oil Research Institute of Malaysia (PORIM), Bangi. 23-28 September 1996. pp. 207-220.

Syed, A.R. & Saleh, A. 1988. Population of Elaeidobius kamerunicus Faust in relation to fruit set. In Proceeding of 1987 International Oil Palm Conferences. Progress and Prospects. Palm Oil Research Institute Malaysia, Kuala Lumpur. 23-26 June 1987. pp. 528-534.

Syed, R.A. 1984. Insect pollinators of African palm. Palmas 5: 19-64.

Syed, R.A. 1982. Insect pollination of oil palm, feasibility of introducing Elaeidobius spp. into Malaysia. Proceeding of the Oil Palm in the Eighties. Kuala Lumpur, Malaysia, 17-20 June 1981. 1: 263-289.

Syed, R.A. 1979. Study on oil palm pollination by insect. Bulletin of Entomolical Research 69: 213-224.

Tan, Y.P. & Basri, M.W. 1985. Another pollinating insect of oil palm - Pyroderces spp. In Proceedings of the Seminar on The Impact of the Pollinating Weevil on The Malaysian Industry. Palm Oil Research Institute of Malaysia, Kuala Lumpur. 21- 24 February 1984. pp. 50-57.

Tuo, Y., Koua, H.K. & Hala, N. 2011. Biology of Elaeidobius kamerunicus and Elaeidobius plagiatus (Coleoptera:Curculionidae) main pollinators of oil palm in West Africa. European Journal of Scientific Research 49(3): 426-423.

Young, A.M. 1982. Population Biology of Tropical Insects. Springer, Boston, MA.

 

*Pengarang untuk surat-menyurat; email: nurulfatihahabdlatip@gmail.com

 

 

 

 

 

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